Climate change was a big part of the announcement Mayor Bloomberg made yesterday endorsing President Obama for reelection.

STEVE INSKEEP, HOST:

Bloomberg owns a media company, is politically independent, and made his endorsement in a memorable way. He said Mitt Romney has taken sensible positions in the past but reversed course on all of them.

MONTAGNE: He also said President Obama's term has been disappointing. But he argued the president was better on a range of issues, especially climate change.

INSKEEP: He said the risk that climate change is linked to Hurricane Sandy and other storms should compel action. NPR's Richard Harris covers climate change issues. Richard, good morning.

RICHARD HARRIS, BYLINE: Good morning.

INSKEEP: So how do President Obama and Mitt Romney differ, if at all, on climate change?

HARRIS: They differ substantially, although if you turn back the clock a few years, the gap is not so great. When Romney was governor of Massachusetts, he was actually a very aggressive advocate for a cap and trade program in the northeastern United States. And as he started to eye an election run in 2008 for president, he decided, oops, this is not a good issue for me and he backed off and he became much more skeptical of climate change.

INSKEEP: This is bringing to mind the health care debate, where Romney as governor of Massachusetts enacted a program that was similar to what the president advocated once he was elected in 2008.

HARRIS: That's right. And if you look at President Obama's position on this, the president has been consistently in favor of doing something about climate change, actually quite aggressively at the beginning of his term, and you may recall he was in Copenhagen for the U.N. climate talks and pushing hard for climate change, and he tried to push something through Congress, a cap and trade bill, that basically was a political quagmire.

And he sort of backed off talking about it on the rhetoric side, but he keeps pushing ahead with policies that make a difference, like dramatically increasing automobile fuel efficiency standards, putting $90 billion of the stimulus into renewable energy programs and so on, so - so he's been working a little bit under the radar, but pushing hard on climate change issues.

INSKEEP: Interesting that you say under the radar. Jeffrey Goldberg of The Atlantic wrote yesterday a little bit sarcastically, I assume: A vote for Obama is a vote for a man who might one day maybe take the lead on climate change. The implication being he's really backed off.

HARRIS: Well, I think it's a political issue, which is that he can't get anything through Congress right now, and there's not a big percentage in talking about climate change. The president talks in terms of clean energy and he talks in terms of increasing jobs and creating an industry that's a clean energy industry. So he's pushing on that. But it is also true that this country, like the rest of the world, is not doing nearly enough to actually slow the course of climate change right now.

These are important steps, but they aren't enough to reduce our emissions by something like 80 percent mid-century, which is the track we really need to be on to stabilize the climate.

INSKEEP: Should we assume for the fact these candidates did not even mention climate change in three different debates that there is no political support for doing very much right now?

HARRIS: There's not a lot of political support. If you look at the issues that the American public cares most about, climate change usually comes in near the bottom. Two-thirds of Americans or more say, yes, the climate is changing and a majority says humans are responsible. But when you say where do you want to put your energy, it's obviously jobs and the economy and these things that affect people every single day.

INSKEEP: But with that, there's been this catastrophic storm that hit Mayor Bloomberg's city, and he does not say it was caused by climate change but he says it may or may not have been. There's a risk that it was. And it's the second time that New York has been slammed by a hurricane in 14 months. How closely can we connect worse storms in the Atlantic with climate change?

HARRIS: Well, what we can say is sea level is rising and it has risen by a bit, which means that storm surges are higher than they would have been a few decades ago. The other thing we can say is that the ocean temperature was warmer than usual, and when you have a warmer ocean, you have a more powerful storm, although how much of that is actually human induced is - well, some of it is, some of it isn't, presumably, in terms of how much the ocean warming here was just a weird anomaly.

So there's presumably an element of climate change to this, but this is not a storm caused by climate change. I think the real issue here, which I think Michael Bloomberg and other people have pointed out, is that we're not prepared for a changing environment and we are going to see more storms like this, more storm surges, rising sea levels. As that's really the issue here, is that as long as we sort of pretend that climate change isn't happening, we're not preparing for it. And the coastal areas certainly pay the price for that.

INSKEEP: And if you live in a city that happens to be mostly on a chain of islands, this could be a concern as time goes on.